Method of anchoraging.



G. E. ROHMER & J. F. BOORAEM.

METHOD OF ANGHORAGING.

APPLICATION FILED APR.24, 1911. RENEWED DBO. 21. 1912.

.1 1 20,4 1 Patented Dec. 8, 191 4 WITNESSES ATTOR EYS,

GABRIEL E. ROI-IMER: OF WOODSIDE,'AND JOHN FRANCIS BOORAEM,

OFFKQ.

on NEW YORK,

N. Y., ASSIGNORS, BY MESNE ASSIGNMENTS, T0 CINCH EXPANSION BOLT & EN-

GINEERING COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

I METHOD OF ANCHORAGING.

To all whom it may concern Be it known that we, GABRIEL E. Ronrrnn, acitizen of the United States of America, and residing in Woods'ide, inthe county of Queens and State of New York, and J oHN FRANCIS BOORAEM, acitizen of the United States, and residing in New York city, borough ofManhattan, county and State of New York, have invented a certain new anduseful Method of Anchoraging, of Wl'llCll the following is a secification.

This invention re ates to anchorages and to those which are usuallytermed expansion anchors, which as is well known are devices in whichtwo or more members, so cooperate that one member moves another membernormally smaller than the hole in which it operates, into such aposition and shape as to be withinv the hole and press against the wallsand thereby engage the same in such a manner as to. withstand the pullon the members.

The invention relates moreparticularly to an im rovement in the art andin the method employed and the. principle underlying the same.

Both these members were usually of a hard material whereby the pressurewas transmitted by one member to the other, or in case one member was ofsoft material it was only sufiiciently soft to yield slightly when undergreat pressure and was not restrained or confined between surroundingmembers. In all such rior devices, the weakest member would of coursebreak first and this usually resulted in the slipping of the entire unitout of the hole or the breaking of that member holding it therein.Usually also these holding-members have only a point-contact or aline-contact, whereby the resistance offered to the piece is acomparatively limited one.

Our invention consists in the application of a soft metal under completerestraint and under continued extreme pressure to an anchorage unit, soarranged and coiiperating with the members of the anchorage unit so thatthe more the unit is pulled, the greater is the hold obtained. since thesoft metal molds itself when confined and under pressure to take up theforce applied and forms so :0 say part of the operatin members, byreason of being moldab e and Specification of Letters Patent.

Patented Dec. 8, 1914. Renewed December 21, 1912. Serial No. 738,081.

always confined and under complete restraint.

It is well known that soft lead is ductile, malleable and viscous, atthe same time incompressible. It is these characteristics which weutilize. With extreme pressure applied and consequent change of formunder the influence of a deforming force, the lead will flow much like-afluid and be capable of movement in every direction, and capable oftransmitting shock equally throughout its parts. The lead when thussubjected to extreme continued pressure while under complete restraintis so manipulated as to press against all arts in contact therewith andby reason 0 pressure on the lead While under confinement it will becomefor all practical purposes one with the several parts. This is obtainedby reason of the pliability of the lead in acting like a fluid whenunder pressure and confinement and creeping into all interstices of thehole to which the anchorage unit is applied, and also molding itselfagainst the bolt and the compressing members cotiperating therewith. Thecontinued and increasing pressure subjects the lead-to the extreme Iacts like an incompressible solid or an incompressible liquid, exceptthat it will not leak like oil or water. It retains increased efiiciencyin resisting shear because of the restraint it is under. Any strain towhich the lead is subjected is transmitted throughout its entire volumeand is dispersed from the parts that produce the strain through to everymolecule. In the accompanying drawings Figure 1 1s a perspective viewwasher prior to the use of it, Fig. 2 is a sectional view, showing thewasher when in use,'and Fig. 3 is an end-view of Fig. 2. There is showna manner in which we utilize the property of the lead to the usefulpurpose described in which the wall 10 to which the member is to beapplied has the hole 11 therein. The bolt 12 is screwthreaded at 13 andengages a formingmember 14 while another forming member 15 rides looselyon the bolt and abutting against a screw-threaded fixed nut 16 engagingthe screw-threads 13. The outer diameter of both of these members is theof the bolt and its J diameter of the hole allowing only cient clearancefor the entrance of the members in'the hole so that they form damsto-preyent any leakage of the soft metal. Betweenthe two members 14. and15 we provide a layer of soft metallic metal, lead for instance, whichmay be in the form. as shown in Fig. 1, and for instance, as acylindrical collar 17 surrounding the bolt 12 mediate the members 14 and15. Any shape may'be given to this layer, it being essential that thevolume ofit should be substantially equal to the volume between themembers 14 and 15 when in their final position. These -members sooperate that the lead therebetween is caused to be'moved and subjectedto pressure which continues until extreme pressure is reached, duringall of -which time all of the lead is under complete restraint. This isdone by revolvin the nut 16 while the bolt 12 is maintaine stationary.When the members I l-and 15 arrive at, the position correspdnding toextreme compression of the lead therebetween, the lead has been forcedinto all the interstices of the hole in the wall and against theinclosing members and bolt and being all the time under completerestraint, the walls of the hole the compressing members of the unit,and the bolt form, so to say, a sin le member or a single piece, thelead so mo ding itself to the parts as to be substantially integraltherewith. The external load is thus equally distributed and fullcylindrical surface contact is obtained, the soft lead causing thecombination of parts to act much like a hydraulic press. The maximumforce of the screw which is limited only by the tensile strength of thebolt being diverted by the s oping wedge-like surface of the .formingmembers, the lead is forced radially upon the inner surface of the wallwith an equal pressure distributed over a smaller area, hence a greaterpressure per square-inch is obtained, thus increasing the frictionbetween the lead and wall, since the reater the normal pressure thegreater the riction. During all this time, the dams or flanges preventleaking and the distribution of the pulling load upon anv infinitenumber of cylindrical planes concentric to the bolt, reduce the tendencyofthelead to shear to a minimum, preventing thereby the shearing strainto be focussed at one cylindrical plane substantially concentric to thebolt.

We have described soft lead and it is necessary that this will be sosoft as to be fully pliable to generally act in the manner described. Wehave found that an alloy of lead and zinc with 20% of zinc acts veryefficiently in the manner described, tests showing that a member asdescribed can withstand 27,800 lbs. on a one inch bolt system, breakingthe bolt, but in no way and inter-' .the expansion. 2. In the artdisturbingthe term orcondition of the lead of the anchorage medium,whilethe rigid shelltype only withstands from. 4,509. to 6,500 lbs. P

We do not limit ourselves to the means shown in the drawings, which showone form in which the property of lead or other substance under completerestraint may be applied to a special and useful purpose, since changesmay be made in themechanical parts and the principle of the inventionstill be retained as disclosed herein and as set forth inthe appendedclaims. The structure forms the subject matter-of our separateapplication, Serial Number 613,627, to which reference is hereby made,the present claims relating only to the new method or art ofanchoraging, and not to the structure by which that method 'may becarried out. Having thus described our invention, we

claim as new and desire to secure by Letters Patent 1. In the art ofanchoring a bolt in a hole in a wall in which an expanding member whosegreatest diameter substantially that of the hole and which 51s heldagainst longitudinal movement on the bolt, engagingly enters into anexpansible member, sa1d expansible member being intermediate theexpanding member and the wall of the hole, and being expanded andpressedoutwardly against said wall by the expanding member, that step whichconsists in spreading the area of application of the expanding force,from the portion to which itis initially applied, to consecutiveportions ofthe expansible member, said expanding force pressing theentire I expansible member outwardly against the wall only at thecompletion of in a wallin which an expanding member whose greatestdiameter is substantially that of the hole and which is held againstlongitudinal movement on the bolt, engagingly enters into an expansiblemember, said expansible member being intermediate the expanding memberand the wall of the hole, and being expanded and pressed outwardlyagainst said wall by the expanding member,

of anchoring a bolt in a hole that step which consists in spreading the,area of application of the expanding force,

from the portion to which it is initially applied, to consecutiveportions of the expansible member, said expanding, force pressing theentire expansible mem er outwardly against the wall only at thecompletion of the expansion, said expansible member be- -mg maintainedstationary during its expansion and-having its material under completerestraint from being moved out of the region of pressure upon theapplication of the said pressure.

3. In the art of anchoring a bolt in a hole a wall in which an expandingmember whose eatest diameter is substantiall that of the ole and whichis held against 0ngitudinal movement on the bolt, engagingly sure andconfining all the moldable material while under restraint.

In testimony, that we claim the forego- 16 ing as our invention, we havesigned our names in presence of two subscribing witmesses.

GABRIEL E. ROHMER. J. FRANCIS BOORAEM.

Witnesses:

JOHN Mormon, L. J. MURPHY.

